Electric lighting device for the drill head of a dental drill



M. KRAUS 2,225,616 ELECTR IC LIGHTING DEVICE FOR THE DRILL HEAD OF A DENTAL DRILL- Dec. 31, 1940.

Filed Oct. 15, 1957 lmenlo Patented Dec. 31, 1940 PATENT OFFICE ELECTRIC LIGHTING DEVICE FOR THE DRILL HEAD or A DENTAL DRILL Michael Kraus, Furth, Bavaria, Germany Application October 13, 1937, Serial No. 168,780 In Germany October 19, 1936 1 Claim.

My invention relates to an electric lighting device for the drill head of a dental drill which is provided with a ball joint and an electric lamp being situated on the drill head. The devices hitherto known have the drawback that the electric lamp is arranged on the drill head in an unsatisfactory manner, whereby a sufficient lighting of the tooth to be treated can not be effected without some trouble in handling the device.

According to my invention this drawback is obviated and a lighting device is created, in which he electric lamp is arranged on the front edge of the drill head, so that the cone of light rays is thrown in the longitudinal direction towards the point of the drill during the treatment of the tooth, whereby the place to be treated is surrounded by light.

Further the electric lamp is arranged changeably on the front edge of the drill head.

The ball joint being inserted between the angle bracket shaft and the drill head is insulated.

The current supply to the movable drill head is obtained by a wire being extended along the angle bracket shaft and provided with a sliding contact,

the sliding spring of which is connected with a sliding ring, said ring is fixed to the part of the ball joint which is situated on the drill head.

Further a contact is provided on the upper edge of the drill head which touches a projection 30 of the socket by insertion on the drill head effecting the closing of the circuit.

The accompanying drawing shows my invention by way of example in which Fig. 1 is a side view,

Fig. 2 is a plan view,

Fig. 3 is a front view of the drill head and Figs. 4-8 are details on an enlarged scale.

According to my invention an electric lamp 0 is arranged in the longitudinal direction of the drill b on the front edge of the drill head a which is connected to the prolongated piece of the angle bracket shaft e. An insulated ball joint 3, f is inserted between the angle bracket shaft e and the drill head a. Said ball joint consists of the part i being fixed to the angle bracket shaft e and of the part I being disposed on the drill head a, so that the latter may be turned towards the axis of the angle bracket shaft. The circuit leading to the lamp at the drill head is conducted along the angle bracket shaft and ends in a sliding contact g, the sliding spring of which is connected with a sliding ring it. This ring it, is fixed to the part I and insulated from this part. The current flows through a cable adapted to the bracket shaft to the sliding contact or and through the ring it and a cable connecting this ring it and the contact member Z of the lamp 0. The return circult of current is through the lamp and the body of the drill and the shaft.

The socket d of the lamp 0 is changeably placed on the drill head a, for which purpose two lateral pins i engaging with two guiding sleeves k on the drill head are provided.

The current connection between the drill head a and the lamp socket d is obtained by providing a contact member I which is arranged at the upper edge of the drill head. The socket d carries a projection m which touches the contact member I when the pins are inserted into the guiding sleeves 7c whereby the circuit is closed.

What I claim is:

A dental drill device, comprising a shaft, a turnable angular drill head connected thereto by a ball joint, an electric lamp mounted on the drill head with its axis parallel to the axis of the drill head, thereby to surround the working place with 

